First Linux commands in Linux CLI - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to list all files and folders in the current directory.

Linux CLI

ls [1]

Drag options to blanks, or click blank then click option'

A-a

B-l

C-h

D-r

Attempts:

3 left

💡 Hint

Common Mistakes

Using -l shows details but not hidden files.

Using -h is for human-readable sizes, not listing all files.

The ls -a command shows all files, including hidden ones.

2fill in blank

medium

Complete the code to change directory to the user's home folder.

Linux CLI

cd [1]

Drag options to blanks, or click blank then click option'

A~

B/root

C/usr

D/etc

Attempts:

3 left

💡 Hint

Common Mistakes

Using /root goes to root user home, not current user.

Using /usr or /etc goes to system folders, not home.

The tilde ~ represents the current user's home directory.

3fill in blank

hard

Fix the error in the command to create a new directory named 'projects'.

Linux CLI

mkdir [1]

Drag options to blanks, or click blank then click option'

Aproject

Bproject-folder

Cproject folder

Dprojects

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'project' instead of 'projects'.

Using names with spaces without quotes causes errors.

The directory name should be projects exactly as intended. Spaces are not allowed without quotes.

4fill in blank

hard

Fill both blanks to display the first 5 lines of a file named 'notes.txt'.

Linux CLI

head [1] [2] notes.txt

Drag options to blanks, or click blank then click option'

A-n

B5

C10

D-c

Attempts:

3 left

💡 Hint

Common Mistakes

Using -c shows bytes, not lines.

Using 10 shows 10 lines, not 5.

The head -n 5 command shows the first 5 lines of the file.

5fill in blank

hard

Fill all three blanks to copy a file named 'report.txt' to a folder named 'backup' and rename it to 'report_old.txt'.

Linux CLI

cp [1] [2]/[3]

Drag options to blanks, or click blank then click option'

Areport.txt

Bbackup

Creport_old.txt

Dreports

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong folder name like 'reports'.

Swapping source and destination.

The command copies report.txt into the backup folder and renames it report_old.txt.

Practice

1. Which Linux command shows the current directory you are in?

easy

A. pwd

B. ls

C. cd

D. mkdir

Solution

1. Step 1: Understand the purpose of pwd

   The pwd command stands for "print working directory" and shows the current folder path.

2. Step 2: Compare with other commands

   ls lists files, cd changes directory, and mkdir creates a folder, so they don't show the current directory.

3. Final Answer:

   pwd -> Option A

4. Quick Check:

   Current directory command = pwd [OK]

Hint: Remember: pwd = print working directory [OK]

Common Mistakes:

• Confusing ls with pwd
• Using cd to show directory
• Thinking mkdir shows current folder

2. Which of the following is the correct syntax to create a new directory named projects?

easy

A. mkdir projects

B. mk projects

C. create projects

D. newdir projects

Solution

1. Step 1: Identify the command to create directories

   The standard Linux command to make a directory is mkdir.

2. Step 2: Check the syntax

   The correct syntax is mkdir directory_name, so mkdir projects is correct.

3. Final Answer:

   mkdir projects -> Option A

4. Quick Check:

   Create directory command = mkdir [OK]

Hint: mkdir means make directory; use it to create folders [OK]

Common Mistakes:

• Using mk instead of mkdir
• Typing create instead of mkdir
• Using newdir which is not a command

3. What will be the output of the following commands?

mkdir testdir
cd testdir
pwd

medium

A. /testdir

B. /home/testdir

C. /home/username/testdir

D. testdir

Solution

1. Step 1: Understand the commands

   mkdir testdir creates a folder named testdir. cd testdir moves into that folder. pwd prints the full path of the current directory.

2. Step 2: Determine the full path

   Assuming the user starts in their home directory (like /home/username), after changing into testdir, pwd will show /home/username/testdir.

3. Final Answer:

   /home/username/testdir -> Option C

4. Quick Check:

   pwd after cd into testdir = full path /home/username/testdir [OK]

Hint: pwd shows full path, not just folder name [OK]

Common Mistakes:

• Expecting just folder name output
• Assuming root directory path
• Confusing relative and absolute paths

4. You run the command cd myfolder but get an error: bash: cd: myfolder: No such file or directory. What is the most likely cause?

medium

A. You do not have permission to use cd

B. The folder myfolder does not exist in the current directory

C. The cd command is misspelled

D. You need to use mkdir before cd

Solution

1. Step 1: Analyze the error message

   The error says "No such file or directory", meaning the folder named myfolder is not found in the current location.

2. Step 2: Check other options

   cd is a basic command and usually not misspelled here. Permissions errors give different messages. mkdir creates folders but is not required before cd if the folder exists.

3. Final Answer:

   The folder myfolder does not exist in the current directory -> Option B

4. Quick Check:

   cd error means folder missing [OK]

Hint: Check folder exists before cd [OK]

Common Mistakes:

• Assuming permission error
• Thinking cd needs mkdir first
• Misspelling cd command

5. You want to create a new folder named backup inside your current directory and then move into it. Which sequence of commands will do this correctly?

hard

A. mkdir
cd backup

B. cd backup
mkdir backup

C. cd backup
cd backup

D. mkdir backup
cd backup

Solution

1. Step 1: Create the folder first

   The command mkdir backup creates the folder named backup in the current directory.

2. Step 2: Change directory into the new folder

   After creating it, cd backup moves you inside that folder.

3. Step 3: Check other options

   cd backup mkdir backup tries to cd into backup before it exists, causing an error. mkdir cd backup misses the folder name in mkdir. cd backup cd backup tries to cd twice without creating the folder.

4. Final Answer:

   mkdir backup cd backup -> Option D

5. Quick Check:

   Create then cd = mkdir then cd [OK]

Hint: Always mkdir before cd into new folder [OK]

Common Mistakes:

• Trying cd before mkdir
• Omitting folder name in mkdir
• Repeating cd without folder